There was once a hand whose fingers were great friends. The owner of this hand started a dangerous job and, despite the care he gave the rest of the fingers, the thumb always came off worse, with lots of cuts and bruises. At first, the other fingers asked the thumb's forgiveness for their clumsiness, and the thumb did indeed forgive them. However, this happened so many times that, one day, the thumb decided to forgive the fingers no more. He stretched himself away from the fingers, and wanted nothing to do with them. Initially, the thumb looked dignified, straight, rigid and aloof. However, that kind of position was forced and ridiculous. The owner even had to keep that hand in his pocket, and there the fingers suffered in darkness and obscurity. Finally, the thumb understood that it had all been his fault, and he asked the fingers' forgiveness, fearful that they would reject him. On the contrary, the fingers easily forgave him, because they - better than anyone - knew that we all make mistakes. Friends once again, all five of them worked together to prove to the owner that they were perfectly well again. Before long, they returned to the light again, this time well aware that they should always forgive each other, and thus avoid ending up inside a gloomy and depressing pocket. 
There is no limit beyond which we should stop practicing forgiveness. 